Toxicity of chlorhexidine on odontoblast-like cells

Chlorhexidine gluconate (chx) is recommended for a number of clinical procedures and it has been pointed out as a potential cavity cleanser to be applied before adhesive restoration of dental cavities. objective: as chx may diffuse through the dentinal tubules to reach a monolayer of odontoblasts that underlies the dentin substrate,this study evaluated the cytotoxic effects of different concentrations of chx on cultured odontoblast-like cells (mdpc- 23). material and methods: cells were cultured and exposed to chx solutions at concentrations of 0.06%,0.12%,0.2%,1% and 2%. pure culture medium (α-mem) and 3% hydrogen peroxide were used as negative and positive control,respectively. after exposing the cultured cells to the controls and chx solutions for 60 s,2 h or 60 s with a 24- h recovery period,cell metabolism (mtt assay) and total protein concentration were evaluated. cell morphology was assessed under scanning electron microscopy. chx had a dose-dependent toxic effect on the mdpc-23 cells. results: statistically significant difference was observed when the cells were exposed to chx in all periods (p<0.05). significant difference was also determined for all chx concentrations (p<0.05). the 60-s exposure time was the least cytotoxic (p<0.05),while exposure to chx for 60 s with a 24-h recovery period was the most toxic to the cells (p<0.05). conclusion: regardless of the exposure time,all chx concentrations had a high direct cytotoxic effect to cultured mdpc-23 cells.